Line reactors are used to isolate electrical components in electrical systems such as motor drives, power supplies, etc. in order to dampen harmonics and transients occurring in power distribution systems. Multiphase line reactors are commonly employed with individual reactors connected in series in multiphase power lines to address common mode and differential mode transients. These line reactor assemblies are typically constructed using a shared core structure with three vertical legs arranged in a common plane and joined by upper and lower horizontal legs, where the three individual phase windings are wound around a corresponding one of the vertical legs. However, these conventional line reactor assembly configurations are bulky and improved designs are desired by which increased short-circuit current ratings are possible without increasing the overall size of the line reactor assembly.